-LRB- CNN -RRB- -- After 18 months of terror and grave devastation , Syrian children are plagued with trauma from witnessing the horrors of war firsthand , an international aid group says .

Save the Children released a report on Tuesday called `` Untold Atrocities , '' a collection of accounts from Syrian refugee children .

`` A massacre took place in my village . Around 25 people were killed -- I witnessed it with my own eyes , '' said Mohamad , 15 , who has fled to Jordan with his family . `` They used different ways to kill people -- electric shocks , throwing machinery and cement blocks on people 's heads . ''

Hassan , 14 , described the use of children as human shields , echoing reports from opposition activists that the Syrian regime had done so .

He said his cousin and uncle died when a rocket `` caused a massacre . ''

`` Almost every child we 've spoken to has seen family members killed , '' Save the Children said .

Even those who survive attacks face dire circumstances .

`` When we were being bombed , we had nothing . No food , no water , no toys -- nothing . There was no way to buy food -- the markets and shops were bombed out , '' Ala'a , 10 , said . `` My father went without food for days because there was n't enough . I remember watching him tie his stomach with rope so he would n't feel so hungry . ''

Wael , 16 , summarized the trauma this way :

`` I have seen children slaughtered . I do n't think I 'll ever be OK again . ''

In other developments :

Diplomatic front : Obama pledges support , Qatar offers a new plan for Syria

U.S. President Barack Obama used his keynote speech at the U.N. General Assembly on Tuesday to pledge American support for those working for a `` common good '' for Syria -- and sanctions against those doing harm .

`` In Syria , the future must not belong to a dictator who massacres his people , '' he said .

`` If there is a cause that cries out for protest in the world today , it is a regime that tortures children and shoots rockets at apartment buildings . And we must remain engaged to assure that what began with citizens demanding their rights does not end in a cycle of sectarian violence . ''

French President Francois Hollande also had strong words on Syria , saying that areas `` liberated '' by opposition forces should be protected by the United Nations .

`` There have been almost 30,000 deaths in the last 18 months -- how many more deaths will we wait for before we act ? How can we allow the paralysis of the United Nations to continue ? '' he asked .

Hollande said France would recognize an opposition government once it is formed , and that the current regime had lost its right to represent the country on the international stage .

France has been at the forefront of international efforts to bring about a resolution in Syria .

In his address to the General Assembly , Qatar Prime Minister Sheikh Hamad bin Jassim Al Thani said the violence in Syria had reached `` an unacceptable phase '' and urged fellow Arab nations to intervene .

`` We have used all available means to get Syria out of the cycle of killing , but that was in vain , '' he said .

In light of the U.N. Security Council 's failure to act effectively , he said , `` It is better for the Arab countries themselves to interfere out of their national , humanitarian , political and military duties and do what it necessary to stop the bloodshed in Syria ... in order to guarantee a peaceful transition of power in Syria . ''

His words come a day after he proposed a `` Plan B '' for solving the Syrian crisis , saying a nonviolent solution is still possible despite more than a year of relentless bloodshed .

In an interview with CNN 's Christiane Amanpour on Monday , Al Thani said the plan would include havens -- which would require a no-fly zone -- and greater humanitarian aid .

`` We wish and we believe that we can solve it peacefully , '' Al Thani said . But , he said , Syrian President Bashar al-Assad has only one solution : `` killing his people to win the war . ''

`` I believe within weeks , we should have a Plan B. And there is a responsibility among us , '' he said . `` We are talking about saving the people of Syria . ''

UK Foreign Secretary William Hague , who spoke to Amanpour on Tuesday , described the situation in the U.N. Security Council with respect to Syria as being at a `` diplomatic impasse . ''

`` We are blocked in the United Nations Security Council from the world being able to put its full weight behind a transitional government in Syria , something that it is obvious solution , obviously part of the solution , '' he said .

Hague was referring to Russia and China , which have repeatedly blocked draft resolutions that would take stronger action against al-Assad 's regime . The secretary is scheduled to meet with Russian leaders this week to discuss the ongoing crisis .

On the ground : Blasts strike a Damascus compound

Dual attacks rattled a Syrian intelligence security compound in Damascus , the regime and opposition activists said Tuesday .

The compound was also the site of a major explosion in March .

Syrian state-run TV said the two improvised explosive devices were `` planted by terrorists '' in a school building and caused seven injuries .

Opposition activists said the Syrian military was using the school building as a base . The new school year has not yet started , Syrian state TV said , so it seems unlikely that children would have been at the site .

In June , Human Rights Watch described cases of `` sexual torture '' at the compound , reported by male and female detainees -- many of whom were political activists or simply attended protests .

At least 148 people were killed across Syria on Tuesday , according to the Local Coordination Committees of Syria , an opposition group .

The highest number of deaths , 44 , was reported in Damascus and its suburbs , where regime forces and rebel fighters are engaged in fierce clashes and communities are under aerial bombardment , the LCC said .

CNN 's Salma Abdelaziz , Saad Abedine , Holly Yan , Samuel Burke and Claire Calzonetti contributed to this report .

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The UK foreign secretary describes the Security Council as being at an impasse

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France 's Hollande says the United Nations should protect `` liberated areas '' in Syria

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Obama : Future `` must not belong to a dictator who massacres his people ''

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`` I have seen children slaughtered . I do n't think I 'll ever be OK again , '' a boy says